2. Diagram of the human Ear

3. Outer Ear - The outer ear is the external portion of the ear, which consists of the pinna, concha, and auditory meatus. It gathers sound energy and focuses it on the eardrum. The visible part is called the pinna. It is composed of a thin plate of yellow elastic cartilage, covered with integument, and connected to the surrounding parts by ligaments and muscles. The concha is the deep, bowl-shaped part of the ear cartilage that attaches directly to the side of the head at the front of the mastoid process of the skull. The opening to the auditory canal is located in the lower front corner of the concha. The concha helps funnel sound into the auditory canal. The auditory meatus (ear canal) is a tube running from the outer ear to the middle ear. Middle Ear - This is a small air-filled space on the inside of the eardrum. There are 3 tiny bones called ossicles in this part. They are called the hammer, anvil and stirrup. They are contained within the middle ear space and serve to transmit sounds from the air to the fluid-filled cochlea.
Inner Ear- The inner ear consists of the cochlea, vestibule, and semi-circular canals. The cochlea propagates these mechanical signals as waves in fluid and membranes, and finally transduces them to nerve impulses which are transmitted to the brain. The vestibule is the central part of the osseous labyrinth, and is situated medial to the tympanic cavity, behind the cochlea, and in front of the semicircular canals. In the middle ear, the energy of pressure waves is translated into mechanical vibrations. The semicircular canals are three half-circular, interconnected tubes located inside each ear. They send messages to your brain to help you keep your balance when you move.

4. Description of how the human ear works
The ear is a key organ of the auditory system that helps in detecting and perceiving sound waves. The parts of the ear turn sound waves into vibrations which are then translated into nerve messages that are sent to the brain. Sound travels into the ear from the external ear. The external ear, or outer ear, is the part of the ear that is visible plus the ear canal. Sound enters the ear through the outer ear and travels to the eardrum. The sound waves cause the eardrum, also called the tympanic membrane, to vibrate. These vibrations pass to the middle ear. The sound vibrations are delivered by a part of the middle ear called the stapes. The inner ear translates the vibrations into nerve messages that are delivered to the auditory nerve which rests at the base of the cochlea. The auditory nerve, named the eighth nerve, carries these messages to the brain, which interprets the impulses as sound.

5. Description of the human frequency response and how it compares to another animal
The number of vibrations that are produced per second is called frequency. Frequency varies for each sound and is measured in hertz. One hertz is equal to one vibration per second. A sound with a low frequency will have a low pitch and a sound with a high frequency will have a high pitch. The range of hearing for a healthy young person is 20 to 20,000 hertz. The hearing range of humans gets worse with age. People lose the ability to hear sounds of high frequency as they get older.
Dog's sense of hearing has an important role within their world. Not only do dogs have a highly developed sense of hearing that can hear a wide range of sounds but they also have the ability to pin point the exact cause of the sound, discriminate between sounds, make an accurate interpretation of the sound, and decided whether it is threatening or non-threatening. The frequencies that dogs can perceive and hear are almost twice that of humans and they can pick up and distinguish sounds at roughly 4 times the range of humans. For example a sound that you can hear at 20 meters a dog can detect pinpoint and interpret at 80 meters. Dogs also have the ability to hear ultra high frequencies that humans cannot and many professional dog handlers and trainers use this ability to their advantage by teaching them and training them to respond to different commands given on whistles that produce ultra high frequency sounds.

6. Two problems that occur with human hearing
Hearing loss: Hearing loss means total or partial hearing inability in one or both ears. It may be temporary or permanent. There are different types of hearing loss such as conductive hearing loss, sensor neural hearing loss, functional hearing loss, central hearing loss and mixed hearing loss. The main causes of hearing loss are ear infections, damage to ear, aging, genetic conditions like hereditary nephritis, as well as some congenital factors like fetal iodine deficiency effects and premature birth. Temporary hearing loss is due to an exposure to loud sounds, ear blockage due to accumulation of ear wax, middle ear infections and damage to the auditory nerve in the brain or the sensory structures of the inner ear due to infections, tumors or skull injuries. Sudden hearing loss is caused by trauma, certain infectious diseases, neurological causes like multiple sclerosis, abnormal tissue growth, circulatory problems in the inner ear and certain medications like birth control pills.
Otitis externa: Infection of external ear is known as otitis externa or swimmer’s ear. It is mainly caused by bacteria, or sometimes by fungi. Excess moisture in the ear due to swimming or humid weather makes the ear more vulnerable for bacterial infection. Frequent swimming, accumulation of ear wax and skin allergies are the risk factors for otitis externa. It causes severe pain, itching, swelling and redness in the outer ear.

7. Technological advancement in treating hearing problems
Without a doubt, the ability to hear and see are two major factors in our quality of life. Hearing loss affects our ability to communicate, sense our surroundings, and enjoy many forms of entertainment. Miniaturization – Hearing aids take full advantage of miniaturization, making hearing aids nearly invisible and more comfortable. All modern aids now utilize microchips with advanced computer programming. It is now quite common to find companies that offer custom-made hearing aids tailored to a patient's specific needs. Digital Signal Processing - Technological advances also allow sounds to be processed instantaneously through digitization. Digitization converts sound to data. Data can then be filtered, altered, or have complex algorithms applied to it before it is converted back to sound again. For example, a patient trying to converse with another person on a busy street will have difficulty hearing that person because of background noise. By processing the sound digitally, the background noise can be reduced while the voice is enhanced, resulting in improved clarity LASIK - LASIK (laser-assisted in situ keratomileusis) is a highly advanced surgical procedure that corrects vision by reshaping the cornea (the clear, curved membrane on the front of the eye) using a computer-controlled laser. The process involves a standard vision correction test, exactly like that used for determining corrective lenses for glasses or contacts, and a corneal map, which is created by projecting concentric rings of light on the cornea